Unable to patch nested gallery

[mayalghamdi]

Hi! 

I have 2 galleries within one bigger gallery, and I want to patch them but the code is not running even though it is not showing any errors. 

A typical patch for my gallery would be

ForAll(Gallery.AllItems, Patch(SPSource, Defaults(SPSource), {ColumnHeader: "Test"}));

So in my nested gallery case, it would be 

ForAll(ParentGal.AllItems, ForAll(ChildGal01.AllItems, Patch(SPSource, Defaults(SPSource), {ColumnHeader: "Test"})));

**This code is only has 1 subgallery for ease of solution, but is meant to have like the scenario suggested 2 subgalleries.

This person has a similar issue to mine but the replies were not relevant. Is something wrong with my logic?

[Daniel_A]

Hello @mayalghamdi,

I haven't tested your solution but I do Imagin that there are som issues for power apps te resolve what instance of gallery one you are targeting.

Try this instead (Sudo-function, not tested):

ForAll(
   ParentGal.AllItems,
      ForAll(
         Filter(
           YourCollection1,
           YourID = ThisRecord.ID), 
            Patch(
             SPSource, 
             Defaults(SPSource), 
             {ColumnHeader: "Test"}
           )
      );
      ForAll(
         Filter(
           YourCollection2,
           YourID = ThisRecord.ID), 
            Patch(
             SPSource, 
             Defaults(SPSource), 
             {ColumnHeader: "Test"}
           )
      )
);

If you are wondering where "ThisRecord" comes from, this is a default variable born when doing a ForAll.

Hope this helps!

Please mark this a the Solution and provide som Kudos, so i know I'm helping 🙂.

[mayalghamdi]

Hey Daniel! 

thank you so much for sharing! And yes there are issues with PowerApps recognizing which gallery youre targeting in a situation like this, hence me proposing the .AllItems property. I want to test out your solution but I am not sure what the collections are. Are you suggesting I collect each smaller gallery in a collection first?

[Daniel_A]

Hello @mayalghamdi,

For optimal performance we normally do a ClearCollect() in visible of the screen or when the app starts, App OnStart. But no I'm not suggesting collecting the smaller galleries.

This follows the following syntax:

ClearCollect(
  colYourCollectionNamn,
  YourDatasource
)

If you havn't done this it's a performance improvment suggestion. Just keep the 2000 row limit in mind.

But never the less, in my mind you have at least two datasources:

• Datasource A
• Datasource B

In the Parent gallery you have Datasource A and in the child you have Datasource B. This means your source for the child gallery should look like this:

Filter(
   Datasource B,
   ParentID = ThisItem.ID // This will filter the datasource to display related rows
)

Otherwise you might have a self referencing lookup, in any case you need to filter in order to disply only related rows in the child gallery.

The same applyes when you need to patch in a ForAll().

Please include some more info if I have come to the wrong conclusion.

Please mark this as the Solution and provide som Kudos, so i know I'm helping 🙂.

[PowerRanger]

@mayalghamdi could you provide a screenshot of your app and describe your datasources so I get a better understanding for what each gallery are used for. 

Please click Accept as solution if my post helped you solve your issue. This will help others find it more readily. It also closes the item. If the content was useful in other ways, please consider giving it Thumbs Up.

[mayalghamdi]

Hey,

I actually only have one source (SPSource = Sharepoint list). My app looks like this
Parent Gallery: no other records than the child galleries
Child Gallery 01: Revenue forecast value 01, Revenue forecast value 02 (for forecast possibility of 50%)
Child Gallery 02: Revenue forecast value 01, Revenue forecast value 02 (for forecast possibility of 90%)

My singular SP list's headers are: Revenue forecast value 01, Revenue forecast value 02, Possibility.

So my expected save methodology should save both galleries using defaults, meaning it saves the first child gallery values using defaults in the sub patch code for Child Gallery 01, patching the revenue values in the perspective column headers in the SP, and patching a text of "Probability 50%". Then does the same thing, saving Child Gallery 02, patching same revenue forecast values, except here its patching a text of "Probability 90%".

my code now

Please let me know if I cleared it any better. 🙂

[mayalghamdi]

Hi Power Ranger, please see in the reply I just posted before this one. I have screenshots and all. Let me know if you need any thing else. 

[Daniel_A]

@mayalghamdi 

Thanks for sharing, I will need to make a test at my end.

Could you also share what the source is of all your galleries please?

Then I'm sure we will solve this issue.

[mayalghamdi]

Hi! My galleries are just a sequence of periods. 

Child galleries' items: 

ForAll(Sequence(PeriodCount.Selected.Value, 0, 1), DateAdd(DateValue(StartingPeriod.Selected.Value), Value, Months))

*PeriodCount is dropdown for how many periods (3 months, 6 months, etc)

*StartingPeriod is date to start with

Parent gallery's items 

Dropdown1.SelectedItems

Regards,

May